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Engine tuning/ bike build

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  • A Arild

    @spookdog
    i get u mate, problem is over here in sweden that whole industry of workshops, small garages, people reboring cylinders and all that is growing smaller by the day, i called a local guy to me to check and he took 80 pounds to rebore the cylinder, however that guy also does work for koenigsegg and theyre cylinders so that might impact his idea of a good price idk, there isnt really anywhere to call over here if u dont know the contacts already sadly, idk how it impacts the engine tbh but i would think if those bushings are loose and worn it would make a clanking noise since the cog wouldnt move aswell together with the rest of the basket if u get what i mean.

    @DTR-NSR as i said above im planning on 3d printing a pair if i get spare time for that, i might make a batch and sell them for 5 pounds or something

    D Offline
    D Offline
    DTR+NSR
    wrote on last edited by
    #33

    @arild said in Engine tuning/ bike build:

    @DTR-NSR as i said above im planning on 3d printing a pair if i get spare time for that, i might make a batch and sell them for 5 pounds or something

    I'd definitely be interested in a set!

    1 Reply Last reply
    0
    • T Offline
      T Offline
      theportingmaster
      wrote on last edited by
      #34

      @arild said in Engine tuning/ bike build:

      80 pounds to rebore the cylinder

      £80 for a rebore is very expensive, Mick Abbey charges £25 for a
      rebore and hone and postage abroad is only £10 as done a few
      cylinders for overseas customers.

      A 1 Reply Last reply
      0
      • T theportingmaster

        @arild said in Engine tuning/ bike build:

        80 pounds to rebore the cylinder

        £80 for a rebore is very expensive, Mick Abbey charges £25 for a
        rebore and hone and postage abroad is only £10 as done a few
        cylinders for overseas customers.

        A Offline
        A Offline
        Arild
        wrote on last edited by
        #35

        @theportingmaster
        Thats a really good price, what shipping company were u using??

        1 Reply Last reply
        0
        • A Offline
          A Offline
          Arild
          wrote on last edited by
          #36

          been a while, ive just recently started doing some work on the bike again, took a long break over the winter, you lose the will to work on the bike when its negative degrees in the garage.

          Ive been getting some stuff going this past week, I was able to go over to my neighbours company/workshop where he had a lathe i was able to use. So I threw together an adapter that is slipfitted over the cylinder skirt, which then centers up in a simple 3-jaw chuck lathe, I did this cause I didn't have access to a four jaw, but that's ofcourse the preferred method to go. I then skimmed and bored the barrel, still have lots to go cause I think a piston had exploded in that barrel before so there's a lot of material missing over the exhaust port.

          https://i.imgur.com/LhPCUF0.mp4

          https://i.imgur.com/usIIdnO.mp4
          Some vids I took at the lathe.

          I also just last night finished up making a port map for my 3mb barrel, I later printed it, cut everything out and used it as a porting guide
          alt text

          As you can see I added some 8mm auxiliary exhaust ports.

          I then just started porting, the only tools I had to use was a normal dremel with a flexshaft and some carbide and diamond burs aswell.
          alt text
          alt text
          alt text
          alt text
          alt text

          Ofcourse its not even close to a perfect port job, but it being my first time without and real porting tools I'm really happy with the result, its not finished yet, the ports need to be cleaned up, barrel needs a rebore which ill do in the lathe this week and the exhaust port needs to be polished cause it got some dings from the dremel. I went conservative with this first iteration, they open at 188 degrees, my main port opens at 200 degrees. Its just a test and if they need to be higher ill raise them a tiny bit.
          I then also need to attack the power valve to get passages for the gases to flow through that aswell.

          Some other stuff I've been working on is an airboot for my 32mm carb so I can use the stock airbox, the opening for the carb is 55mm compared to the roughly 38mm stock carb and boot. No matter how much heat or force used it didn't fit.
          alt text

          My tacho fixture on the case had also been stripped so took an hour to mock a new model up in solidworks so I could 3dprint
          alt text

          I was also able to pick some wr426f forks up for free, however the shape they're in isn't the best, the aluminium has corroded and pitted all over the fork tubes, its nothing deep tho so its only visual, so whenever I get a front axle for it and get the bearing cup made I'm chucking them on aswell

          CalumC 1 Reply Last reply
          2
          • A Arild

            been a while, ive just recently started doing some work on the bike again, took a long break over the winter, you lose the will to work on the bike when its negative degrees in the garage.

            Ive been getting some stuff going this past week, I was able to go over to my neighbours company/workshop where he had a lathe i was able to use. So I threw together an adapter that is slipfitted over the cylinder skirt, which then centers up in a simple 3-jaw chuck lathe, I did this cause I didn't have access to a four jaw, but that's ofcourse the preferred method to go. I then skimmed and bored the barrel, still have lots to go cause I think a piston had exploded in that barrel before so there's a lot of material missing over the exhaust port.

            https://i.imgur.com/LhPCUF0.mp4

            https://i.imgur.com/usIIdnO.mp4
            Some vids I took at the lathe.

            I also just last night finished up making a port map for my 3mb barrel, I later printed it, cut everything out and used it as a porting guide
            alt text

            As you can see I added some 8mm auxiliary exhaust ports.

            I then just started porting, the only tools I had to use was a normal dremel with a flexshaft and some carbide and diamond burs aswell.
            alt text
            alt text
            alt text
            alt text
            alt text

            Ofcourse its not even close to a perfect port job, but it being my first time without and real porting tools I'm really happy with the result, its not finished yet, the ports need to be cleaned up, barrel needs a rebore which ill do in the lathe this week and the exhaust port needs to be polished cause it got some dings from the dremel. I went conservative with this first iteration, they open at 188 degrees, my main port opens at 200 degrees. Its just a test and if they need to be higher ill raise them a tiny bit.
            I then also need to attack the power valve to get passages for the gases to flow through that aswell.

            Some other stuff I've been working on is an airboot for my 32mm carb so I can use the stock airbox, the opening for the carb is 55mm compared to the roughly 38mm stock carb and boot. No matter how much heat or force used it didn't fit.
            alt text

            My tacho fixture on the case had also been stripped so took an hour to mock a new model up in solidworks so I could 3dprint
            alt text

            I was also able to pick some wr426f forks up for free, however the shape they're in isn't the best, the aluminium has corroded and pitted all over the fork tubes, its nothing deep tho so its only visual, so whenever I get a front axle for it and get the bearing cup made I'm chucking them on aswell

            CalumC Offline
            CalumC Offline
            Calum
            wrote on last edited by
            #37

            @arild Lovely bud!

            Are you going to make match holes in the powervalve as well? Or are you running open port?

            Always Originate, Never Pirate!

            A 1 Reply Last reply
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            • CalumC Calum

              @arild Lovely bud!

              Are you going to make match holes in the powervalve as well? Or are you running open port?

              A Offline
              A Offline
              Arild
              wrote on last edited by
              #38

              @calum I havent really decided that yet, i want to be able to run the pv but I'm not sure how to do it with the auxiliaries in a good way, ideally id like the ports to stay closed and open up with the rest of the valve, idk how well that will work tho so I might just resort to having the open all the time

              T 1 Reply Last reply
              0
              • A Arild

                @calum I havent really decided that yet, i want to be able to run the pv but I'm not sure how to do it with the auxiliaries in a good way, ideally id like the ports to stay closed and open up with the rest of the valve, idk how well that will work tho so I might just resort to having the open all the time

                T Offline
                T Offline
                theportingmaster
                wrote on last edited by
                #39

                @arild Added boost ports and modified powervalve to suit, can
                upload port maps to add boostports.
                111.JPG

                juj.JPG

                CalumC 1 Reply Last reply
                1
                • T theportingmaster

                  @arild Added boost ports and modified powervalve to suit, can
                  upload port maps to add boostports.
                  111.JPG

                  juj.JPG

                  CalumC Offline
                  CalumC Offline
                  Calum
                  wrote on last edited by
                  #40

                  @theportingmaster that looks pucker mate!

                  Let us know how the bike rides after.

                  Always Originate, Never Pirate!

                  T 1 Reply Last reply
                  0
                  • CalumC Calum

                    @theportingmaster that looks pucker mate!

                    Let us know how the bike rides after.

                    T Offline
                    T Offline
                    theportingmaster
                    wrote on last edited by
                    #41

                    @calum Will be getting it dynoed at Mick Abbeys in a couple of weeks so will upload dyno results and video of its power run once
                    sorted. cheers Terry

                    A 1 Reply Last reply
                    1
                    • T theportingmaster

                      @calum Will be getting it dynoed at Mick Abbeys in a couple of weeks so will upload dyno results and video of its power run once
                      sorted. cheers Terry

                      A Offline
                      A Offline
                      Arild
                      wrote on last edited by
                      #42

                      @theportingmaster
                      that's looking real good mate, certainly way better than my porting

                      1 Reply Last reply
                      0
                      • D Offline
                        D Offline
                        detsinomistaja
                        wrote on last edited by
                        #43

                        Would Boosted port 3mb cylinder work if im having DEP exhaust and 30mm chinese PWK? Would i get noticeable power gains? I have an friend who could port the cylinder and make boost ports.

                        D 1 Reply Last reply
                        0
                        • D detsinomistaja

                          Would Boosted port 3mb cylinder work if im having DEP exhaust and 30mm chinese PWK? Would i get noticeable power gains? I have an friend who could port the cylinder and make boost ports.

                          D Offline
                          D Offline
                          detsinomistaja
                          wrote on last edited by
                          #44

                          @detsinomistaja He also could modify them YPVS flanges to work with boost ports.

                          1 Reply Last reply
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